Method of laminating fuel cell-use separator and film/electrode junction element and device therefor

ABSTRACT

The present method corrects a warp in a separator ( 78 ) applied with a sealant ( 97 ) during production of fuel cells. The correction is performed at a correcting device ( 47 ). With the warp being corrected at the correcting device, a membrane/electrode assembly is superimposed on the separator.

TECHNICAL FIELD

[0001] The present invention relates to a method of laminating aseparator and a membrane/electrode assembly for fuel cells and anapparatus for laminating the same, which are suitable for obtaining goodsealing in fuel cells.

BACKGROUND ART

[0002] Fuel cells utilize the reverse principle of the electrolysis ofwater, causing chemical reactions between hydrogen and oxygen, andproducing electricity. Only water is theoretically discharged therefrom.Hydrogen is generally expressed as a fuel gas. Air is generally used asan oxygen supply source and expressed as an oxidant gas.

[0003] As such a fuel cell, a “Fuel Cell” disclosed in, for example,Japanese Patent Laid-Open Publication No. 2000-123848 is known. Thisfuel cell is configured to form a cell module by interposing anelectrolyte membrane between an anode electrode and a cathode electrodeand interposing the anode electrode and the cathode electrode between afirst separator and a second separator via gaskets provided at the outersides of the electrodes, respecttively.

[0004] More specifically, a first flow path constituting a flow path ofa fuel gas is formed on an internal surface of the first separator and asecond flow path constituting a flow path of an oxidant gas is formed onan internal surface of the second separator, which supply a fuel gas andan oxidant gas to the middle electrolyte membrane, respectively.

[0005] Since an electric power obtained from a single cell module isvery small, a plurality of such cell modules are stacked on one anotherto obtain a desired electric power. The first and second separators areseparating members for preventing the leakage of a fuel gas or anoxidant gas into adjacent cells, thus being called as “separators.”

[0006] The first separator has on its internal surface the first flowpath for a fuel gas and the second separator has on its internal surfacethe second flow path for an oxidant gas. It is required to provide thefirst and second flow paths with a plurality of very shallow grooves inorder to effectively bring the gases into contact with the anodeelectrode and the cathode electrode.

[0007] The first and second separators have at one ends a fuel gassupply hole and an oxidant gas supply hole for supplying a fuel gas andan oxidant gas to the first and second flow paths, respectively, andhave at the other ends a fuel gas discharge hole and an oxidant gasdischarge hole, respectively. The first and second separators also haveat the one ends cooling water supply holes for letting in cooling waterand have at the other ends cooling water discharge-holes.

[0008] The prevent inventors have made various attempts to produce acell module by applying a liquid sealant instead of two gaskets toseparators and interposing a membrane/electrode assembly consisting ofan electrolyte membrane and electrodes between two separators, beingconfronted with a problem as described below.

[0009]FIGS. 18A and 18B illustrate a laminating process of twoseparators and a membrane/electrode assembly.

[0010] In FIG. 18A, a separator 203 applied with a sealant 202 is placedon a laminating station 201, a membrane/electrode assembly 206consisting of an electrolyte membrane 204 and carbon electrodes 205, 205attached to the opposite surfaces of the electrolyte membrane 204 issuperimposed on the separator 203, and another separator 207 appliedwith a sealant 202 is superimposed on the membrane/electrode assembly206, forming a lamination of the separator 203, membrane/electrodeassembly 206 and separator 207, and thus producing a cell.

[0011] In FIG. 18B, the sealants 202, 202 applied to edge portions ofthe separators 203 and 207 are spread out by lamination. Since theseparators 203 and 207 are warped toward each other, the outer thicknessof the sealant 202 is t1 and the inner thickness thereof is t2 that isthinner than t1. The thinner the thickness of the carbon electrodes 205,205, the thin part of the sealant 202 becomes thinner, preventing goodsealing.

[0012] It is thus desired to improve a method of laminating a separatorand a membrane/electrode assembly for fuel cells and an apparatus forlaminating the same so as to obtain good sealing in fuel cells.

DISCLOSURE OF THE INVENTION

[0013] According to the present invention, there is provided a method oflaminating a separator and a membrane/electrode assembly for fuel cells,in which the membrane/electrode assembly is superimposed on theseparator applied with a sealant in a laminating station, which methodcomprises the steps of: correcting a warp in the separator at acorrecting device annexed to the laminating station; and superimposingthe membrane/electrode assembly on the separator with the correctingdevice being operated.

[0014] A separator formed only on one surface with grooves constitutinggas flow paths and the like, or formed on one surface with groovesdifferent in shape from grooves formed on the other surface can bewarped. Even if the warp is once corrected, the separator made fromresin, for example, is again elastically warped.

[0015] In the present invention, since the membrane/electrode assemblyis superimposed on the separator while the separator is corrected withthe correcting device being operated, the sealant applied to theseparator can be spread out to an even thickness, providing goodsealing.

[0016] The warp in the separator is preferably corrected by attractingand flattening the separator under a negative pressure formed by jettingof a compressed air at the correcting device. The correcting deviceconfigured to discharge the compressed air in jets prevents theattracted separator from contacting the correcting device, and will notdamage the separator.

[0017] In the present invention, the negative pressure formed at thecorrecting device is preferably controlled so as to reduce the height ofthe separator between a sealant-applied surface applied with the sealantand a corrected surface to be corrected in warping, to or below apredetermined value. Thus reducing the height between thesealant-applied surface and the corrected surface to or below apredetermined value by controlling the negative pressure at thecorrecting device allows easy setting of the height only by adjustingthe amount of jets of the compressed air, varying the negative pressure.Preparation in the lamination process thus becomes easy, improvingworkability.

[0018] According to the present invention, there is further provided anapparatus for laminating a separator and a membrane/electrode assemblyfor use as a fuel cell, which apparatus comprises: a pallet on which theseparator applied with a sealant is placed; and a correcting device forcorrecting a warp in the separator; wherein, the membrane/electrodeassembly is superimposed on the separator with the correcting devicebeing operated. As described above, the correcting device emits thecompressed air in jets. The laminating apparatus of such a simplestructure is obtained.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019]FIG. 1 is a front view of a sealant-application and laminationapparatus for fuel cell separators according to the present invention;

[0020]FIG. 2 illustrates a sealant applying station shown in FIG. 1;

[0021]FIG. 3 is a view of an arrow 3 in FIG. 2;

[0022]FIG. 4 is a view of an arrow 4 in FIG. 2, illustrating a separatormount;

[0023]FIGS. 5A and 5B illustrate a correcting device for correcting awarp in a separator;

[0024]FIG. 6 is a plan view of a pallet for carrying the separator;

[0025]FIG. 7 is an enlarged cross-sectional view taken along line 7-7 inFIG. 6;

[0026]FIG. 8 is an enlarged cross-sectional view taken along line 8-8 inFIG. 6;

[0027]FIG. 9 is an enlarged cross-sectional view taken along line 9-9 inFIG. 6;

[0028]FIG. 10 is a flow diagram of the application of a sealant to theseparator and lamination;

[0029]FIGS. 11A to 11C are explanatory views of positioning theseparator on the pallet;

[0030]FIG. 12 is an explanatory view of placing a pallet mount onto theseparator mount;

[0031]FIGS. 13A to 13D are partial diagrams illustrating the sequence ofpositioning the pallet on pallet mounting portions;

[0032]FIGS. 14A and 14B are schematic diagrams illustrating thecorrection of a warp in the separator with the correcting device;

[0033]FIG. 15 is a diagram illustrating the application of a sealant tothe separator with the separator being corrected;

[0034]FIGS. 16A to 16H are diagrams illustrating the process of applyinga sealant between an application-start portion and an application-endportion during the application of the sealant to the separator;

[0035]FIGS. 17A to 17C are schematic diagrams illustrating the sequenceof superimposing a membrane/electrode assembly on a separator in alaminating station; and

[0036]FIGS. 18A and 18B are schematic diagrams illustrating aconventional way of laminating separators and a membrane/electrodeassembly.

BEST MODE FOR CARRYING OUT THE INVENTION

[0037] As shown in FIG. 1, a sealant-application and laminationapparatus 10 for fuel cell separators has a sealant applying station 11for applying a sealant to a separator and a laminating station 12 forsuperimposing a membrane/electrode assembly on a separator applied witha sealant.

[0038] A membrane/electrode assembly (hereinafter referred to as an“MEA”) is configured by attaching an anode electrode and a cathodeelectrode of carbon papers to the opposite surfaces of a high polymerelectrolyte membrane of a high molecular compound.

[0039] FIGS. 2 to 4 illustrate the sealant applying station 11 shown inFIG. 1. The sealant applying station 11 includes a separator mount 22mounted on a base 21, an arm 23 mounted on the base 21, a sealantapplying gun 24 mounted to the arm 23, and a non-contact sensor 25disposed in the vicinity of the distal end of the sealant applying gun24.

[0040] The sealant applying gun 24 includes a replaceable sealantcartridge 27 storing a sealant, a sealant supply hose 28 attached to thesealant cartridge 27, a sealant extruder 31 connected to the distal endof the sealant supply hose 28, an electric motor 32 for driving thesealant extruder 31, and a nozzle 33 attached to the distal end of thesealant extruder 31 for discharging the sealant.

[0041] The non-contact sensor 25 irradiates a separator surfaceapproximately below the nozzle 33 with, for example, a laser, detectingan already-applied sealant without contacting it during the applicationof the sealant to the separator. A controller not shown controls thehorizontal and vertical movement of the sealant applying gun 24 byactuating the arm 23 based on a signal from the non-contact sensor 25.

[0042] The sealant extruder 31 of the sealant applying gun 24 has ascrew with a spiral groove inserted into a cylinder. The screw isrotated with the electric motor 32 to suck a sealant within the sealantcartridge 27 via the sealant supply hose 28 and extrude the sealant frombetween the inner wall of the cylinder and the screw groove to bedischarged from the nozzle 33.

[0043] As shown in FIG. 3, a back board 35 is attached to the rear ofthe sealant applying gun 24. A pair of stays 36 (the stay 36 behind isnot shown) are extended obliquely downward from a lower end of the backboard 35. The non-contact sensor 25 is attached to the distal ends ofthe stays 36. The distal end of the non-contact sensor 25 is orienteddownward of the nozzle 33.

[0044]FIG. 4 illustrates the sealant applying station viewed from thetop.

[0045] The separator mount 22 of the sealing application station 11 haspallet mounting portions 41, 42, 43 and 44 on which a pallet 81 (seeFIG. 6) for carrying a separator is placed, a first locating member 45and a second locating member 46 for positioning the pallet 81 on theseparator mount 22, and correcting devices 47, 47 as correcting meansfor correcting a warp in a separator mounted on the pallet 81.

[0046] The pallet mounting portion 41 has a mounting surface 51 and anL-shaped protrusion 52 protruded from the mounting surface 51. TheL-shaped protrusion 52 has locating surfaces 52 a and 52 b.

[0047] The pallet mounting portion 42 has a mounting surface 53 and arectangular protrusion 54 protruded from the mounting surface 53. Therectangular protrusion 54 has a locating surface 54 a.

[0048] The pallet mounting portions 43 and 44 have mounting surfaces 55and 56, respectively.

[0049] The first locating member 45 includes a cylinder portion 61, rods62, 62 inserted into cylinders not shown within the cylinder portion 61,and a presser 63 attached to the distal ends of the rods 62, 62. Thefirst locating member 45 supplies oil or air from inlets 64, 64 into thecylinders to push out the rods 62, 62, pressing a part of the pallet 81with the presser 63, and positioning the pallet 81. Reference numeral 63a denotes an oblique surface formed on the presser 63.

[0050] The second locating member 46 includes a cylinder portion 66,rods 67, 67 inserted into cylinders not shown within the cylinderportion 66, and a presser 68 attached to the distal ends of the rods 67,67. The second locating member 46 supplies oil or air from inlets 69, 69into the cylinders to push out the rods 67, 67, pressing a part of thepallet 81 with the presser 68, and positioning the pallet 81. Referencenumeral 68 a denotes an oblique surface formed on the presser 68.

[0051]FIGS. 5A and 5B illustrate the correcting device 47 for fuel cellseparators shown in FIG. 4.

[0052] In FIG. 5A, the correcting device 47 includes a cylindricalportion 72, a joint pipe 75 connected to a plurality of jet orifices 74formed in the cylindrical portion 72, opening along the edge of an uppersurface 73, and an air hose 76 connected to the joint pipe 75.

[0053] In FIG. 5B, a compressed air is supplied through the air hose 76,and the air jets out through the joint pipe 75 and the plurality of jetorifices 74. When a separator 78 is brought close to the correctingdevice 47, the air swiftly flows out from between the edge of thecylindrical portion 72 and the separator 78 as shown by arrows {circleover (1)}, {circle over (1)}. This causes a negative pressure between acentral portion of the upper surface 73 of the cylindrical portion 72and the separator 78, drawing the separator 78 toward the cylindricalportion 72 as shown by arrows {circle over (2)}. The jets of air fromthe jet orifices 74 prevent the separator 78 from contacting the uppersurface 73 of the cylindrical portion 72.

[0054] Specifically, the correcting device 47 can attract the separator78 at a distance without contacting the separator 78, correcting a warpin the separator 78.

[0055] Further, since the correcting device 47 does not contact theseparator 78, no metal ions are attached to the separator 78. If metalions are attached to the separator 78, they would be attached to carbonelectrodes of an MEA superimposed on the separator 78, combining withelectrons, and depositing a metal on the carbon electrodes. Thedeposited metal can prevent a reaction between hydrogen and oxygen,degrading the performance of the fuel cell.

[0056]FIG. 6 illustrates a pallet viewed from the top for carrying thefuel cell separator 78 according to the present invention. The pallet 81as a carrying member includes a frame 82. The frame 82 has locating pins83, 83 for positioning the separator 78, a plurality of hooks 84 forfixing the separator 78, and a plurality of locating blocks 85 forlocation on the separator mount 22 shown in FIG. 4. The frame 82 hashandles 86, 86 at its opposite ends.

[0057]FIG. 7 illustrates the locating block 85 fixed to the undersurfaceof the frame 82 with a screw 91. The locating block 85 is, as also shownin FIG. 6, a cylindrical member.

[0058] As shown in FIG. 8, the hook 84 includes a separator fasteningpiece 94 and a collar 95. The separator fastening piece 94 is attachedto the upper surface of the frame 82 via the collar 95 with a bolt 93.

[0059] The height of a step 95 a of the collar 95 is set greater thanthe thickness of the separator fastening piece 94. The separatorfastening piece 94 is thus rotatable about the collar 95 fixed to theframe 82 by fastening the bolt 93. Reference numeral 94 a denotes anotch formed on the undersurface of the separator fastening piece 94, tobe engaged on an edge portion of the separator 78.

[0060]FIG. 9 illustrates the locating pin 83 driven into the uppersurface of the frame 82, and the locating hole 78 a of the separator 78fitted onto the locating pin 83.

[0061]FIG. 10 is a flow diagram of a sealant application to a separatorfor fuel cells and lamination according to the present invention.

[0062] Step (hereinafter abbreviated as ST) 01: A separator ispositioned on a pallet.

[0063] ST02: The pallet carries the separator.

[0064] ST03: The pallet is positioned in the sealant applying station.That is, the separator is positioned in the sealant applying station.

[0065] ST04: With a warp in the separator corrected, a sealant isapplied to the separator.

[0066] ST05: The pallet carries the separator.

[0067] ST06: The pallet is positioned in the laminating station.

[0068] ST07: With a warp in the separator corrected, an MEA issuperimposed on the separator. A plurality of cells are produced in thismanner and stacked on one anther to produce a fuel cell.

[0069]FIGS. 11A to 11C illustrate the separator 78 positioned on thepallet 81.

[0070] As shown in FIG. 11A, the locating holes 78 a, 78 a of theseparator 78 are first fitted onto the locating pins 83, 83 of thepallet 81 to position the separator 78 on the pallet 81.

[0071] As shown in FIG. 11B, the separator fastening piece 94 of thehook 84 provided on the pallet 81 is rotated as shown by an arrow,engaging the notch 94 a of the separator fastening piece 94 on an edgeportion of the separator 78 as shown in FIG. 11, and fastening the edgeportion of the separator 78.

[0072] As shown in FIG. 12, the locating blocks 85 provided at fourcorners of the pallet 81 are placed on the pallet mounting portions 41,42, 43 and 44 of the separator mount 22.

[0073]FIGS. 13A to 13D illustrate the positioning of a pallet at thepallet mounting portion 41.

[0074] As shown in FIG. 13A, the locating block 85 is placed on themounting surface 51 at a distance from the locating surfaces 52 a and 52b of the L-shaped protrusion 52 of the pallet mounting portion 41.

[0075] As shown in FIG. 13B, the locating block 85 is placed on themounting surface 53 at a distance from the locating surface 54 a of therectangular protrusion 54 of the pallet mounting portion 42.

[0076] As shown in FIG. 13C, the presser 63 is advanced toward theL-shaped protrusion 52 as shown by an arrow via the rods 62, 62 bysupplying oil or air to the cylinder portion 61, to bring the obliquesurface 63 a of the presser 63 into contact with the locating block 85.The locating block 85 receives component forces in leftward and upwarddirections in the figure applied from the oblique surface 63 a, movingleftward and upward as shown by arrows.

[0077] As shown in FIG. 13D, the presser 68 is advanced toward therectangular protrusion 54 as shown by an arrow via the rods 67, 67 bysupplying oil or air to the cylinder portion 66, to bring the obliquesurface 68 a of the presser 68 shown in FIG. 13B into contact with theblock 85 nearly simultaneously with the contact of the oblique surface63 a shown in FIG. 13A to the locating block 85. The locating block 85receives component forces in leftward and upward directions in thefigure applied from the oblique surface 68 a, moving leftward and upwardas shown by arrows.

[0078] In FIGS. 13C and 13D, with the pressers 63 and 68 continuouslymoved, the oblique surfaces 63 a, 68 a make the locating block 85 shownin FIG. 13A abut on the locating surfaces 52 a and 52 b and the locatingblock 85 shown in FIG. 13B abut on the locating surface 54 a. At thattime, an amount of clearance C occurs between a side surface 63 b of thepresser 63 and the locating block 85 as shown in FIG. 13C, with thelocating block 85 being supported at three places on the locatingsurfaces 52 a and 52 b and the oblique surface 63 a.

[0079] The locating blocks 85, 85 placed on the mounting surface 55 ofthe pallet mounting portion 43 and the mounting surface 56 of the palletmounting portion 44 shown in FIG. 12 move with the movement of thelocating blocks 85, 85 placed on the above-described mounting surfaces51 and 53. In this manner, the positioning of the pallet 81 on theseparator mount 22 is completed.

[0080]FIGS. 14A and 14B illustrate the correction of a warp in theseparator 78 with the correcting device 47.

[0081]FIG. 14A illustrates that the correcting device 47 is disposedbelow the separator 78 placed on the pallet 81. One of the twocorrecting devices 47 is omitted for convenience. A separator 78 formedonly on one surface with grooves constituting gas flow paths and thelike, or a separator 78 formed on one surface with grooves different inshape from grooves formed on the other surface suffers warping as shownin the figure.

[0082] As shown in FIG. 14B, to correct the warp in the separator 78, acompressed air is supplied to the correcting device 47 to jet out frombetween the correcting device 47 and the separator 78 as shown byarrows, attracting the separator 78 with the correcting device 47. As aresult, the separator 78 becomes flat as shown by a hollow arrow.

[0083]FIG. 15 illustrates the application of a sealant 97 to theseparator 78 with the separator 78 being corrected.

[0084] With the warp in the separator 78 corrected, that is, with thecorrecting devices 47 (see FIG. 14B) operated, the sealant 97 is appliedto the separator 78. The sealant 97 is initially applied in the vicinityof the locating hole 78 a (97 a denotes an application-start portion),for example, and is applied in a rectangular shape to the insidegenerally along the edge of the separator 78 as shown by arrows. Anapplication-end portion 97 b is crossed over the application-startportion 97 a.

[0085]FIGS. 16A to 16H illustrate the process of applying a sealant inthe vicinity of an intersecting position between the application-startportion 97 a and the application-end portion 97 b during the applicationof the sealant 97 to the separator 78.

[0086] In FIG. 16A, the nozzle 33 of the sealant applying gun moveswhile applying the sealant 97 to the separator 78, maintaining a heighthi from the separator 78.

[0087] In FIG. 16B, the nozzle 33 comes close to the application-startportion 97 a of the sealant 97. When a laser 99 emitted from thenon-contact sensor 25 shown in FIG. 3 detects the application-startportion 97 a of the sealant 97, the nozzle 33 starts moving downward asshown by an arrow. The nozzle 33 moves downward to the position of aheight h2 from the separator 78 as shown in FIG. 16C, and then thenozzle 33 starts moving upward as shown by an arrow.

[0088] In FIG. 16D, upon reaching the original height h1 from theseparator 78 (see FIG. 16A), the nozzle 33 again moves horizontally asshown by an arrow, maintaining the height h1.

[0089] As shown by arrows in FIGS. 16E and 16F, the nozzle 33 continuesapplying the sealant 97 while horizontally moving, and finishes theapplication of the sealant 97 as shown in FIG. 16G. At an intersectingportion 97 c between the application-start portion 97 a and theapplication-end portion 97 b shown in FIG. 16G, a gap 101 is produced onthe left of the application-start portion 97 a (on the side behind theintersection). No gap is produced on the right of the application-startportion 97 a (on the side in front of the intersection), resulting inimproved sealing.

[0090] In order to fill in the gap 101 on the left of theapplication-start portion 97 a, it is possible to return the nozzle 33to a position where the sealant-application position is crossed over theapplication-start portion 97 a as shown in FIG. 16, that is, a positionhorizontally distanced by a predetermined distance L from the locationof the vertically moving nozzle 33 shown in FIG. 16D, for example, andthen lower the nozzle 33 to the position of a height h3 from theseparator 78 (h3<h1 or h3=h2).

[0091] Thereafter, the attraction of the separator 78 with thecorrecting device 47 shown in FIG. 14B is stopped, and the separator 78applied with the sealant 97 is carried on the pallet 81 (see FIG. 6) tothe laminating station.

[0092] The laminating station 12 shown in FIG. 1 has a separator mountconfigured the same as the separator mount 22 shown in FIG. 4. Asdescribed in FIGS. 12 and 13A to 13D, the pallet 81 is positioned on theseparator mount of the laminating station 12.

[0093]FIGS. 17A to 17C schematically illustrate the sequence ofsuperimposing an MEA on a separator in the laminating station.

[0094]FIG. 17A illustrates the pallet 81 placed on the separator mountof the laminating station. The separator 78 applied with the sealant 97is almost returned to a warped state shown in FIG. 14A. The heightbetween a sealant-applied surface and a corrected surface to becorrected in warping, that is, the distance between a point A on anupper surface of the separator 78 (a point corresponding to the centerof the width of the sealant 97) and a point B (the top of the warpedseparator 78, that is, a corrected position of the separator 78) shownin the figure is D.

[0095] In FIG. 17B, a compressed air is supplied to a correcting device47 provided at the laminating station to jet out from between thecorrected device 47 and the separator 78 as shown by arrows, whereby thecorrecting device 47 attracts the separator 78. The distance D shown inFIG. 17A is reduced to or below a predetermined value. It is desirableto reduce the distance D to zero to flatten the separator 78.

[0096] With the separator 78 being attracted for correction, an MEA 103is placed on a surface of the separator 78 applied with the sealant 97,and another separator 104 already applied with a sealant 97 is placed onthe upper surface of the MEA 103, and then a frame member 105 is placedon the separator 104.

[0097] In FIG. 17C, the separator 78, MEA 103 and separator 104superimposed on one another are pressed via the frame member 105 asshown by arrows with a pressing device 107 shown in FIG. 1, producing acell.

[0098] Pressing via the frame member 105 without the correcting device47, for example, could flatten the separator 78 to some degree. However,the frame member 105 could not press a central portion of the separator78, preventing the entire flattening of the separator 78.

[0099] In the present invention, since the separator 78 is correctedwith the correcting device 47 to be sufficiently flat and then pressedwith the frame member 105, the sealant 97 is spread out on a flatsurface.

[0100] As described in FIGS. 17A to 17C, the present invention ischaracterized in that, in a method of laminating the fuel cell separator78 and the MEA 103 in which the MEA 103 is superimposed on the separator78 applied with the sealant 97 in the laminating station 12 (see FIG.1), the correcting device 47 annexed to the laminating station 12corrects the warp in the separator 78, and the MEA 103 is superimposedon the separator 78 with the correcting device 47 operated. The sealant97 applied to the separator 78 can be spread out to an even thickness,providing good sealing.

[0101] The correcting device 47 of the present invention ischaracterized by attracting the separator 78 for flattening under anegative pressure formed by jetting of a compressed air. The separator78 attracted is thus prevented from contacting the correcting device 47and will not be damaged.

[0102] The present invention is further characterized in that a negativepressure formed at the correcting device 47 is controlled so that thevertical distance D of the separator 78 between the point A on thesealant-applied surface applied with the sealant 97 and the point B onthe corrected surface to be corrected in warping is reduced to or belowa predetermined value. To reduce the distance D to or below thepredetermined value (the distance D is zero at minimum, in which casethe separator 78 is flattened), only adjusting the amount of jets of acompressed air can vary the negative pressure, easily setting thedistance D. Preparation in the lamination process thus becomes easy,improving workability.

[0103] Correcting means of the present invention is not limited to thecorrecting device 47 shown in the embodiment, and may be a combinationof air jetting means and air sucking means.

Industrial Applicability

[0104] In the present invention, a correcting device annexed to alaminating station corrects a warp in a separator, and amembrane/electrode assembly is superimposed on the separator with thecorrecting device being operated, so that a sealant applied to theseparator can be spread out to an even thickness, providing goodsealing. This is advantageous in the production of fuel cells.

1. A method of laminating a separator (78) and a membrane/electrodeassembly (103) for fuel cells, in which said membrane/electrode assemblyis superimposed on said separator applied with a sealant (97) in alaminating station (12), said method comprising the steps of: correctinga warp in said separator at a correcting device (47) annexed to saidlaminating station; and superimposing said membrane/electrode assemblyon said separator with said correcting device being operated.
 2. Alaminating method as set forth in claim 1, wherein said warp in saidseparator (78) is corrected by attracting and flattening said separatorunder a negative pressure formed by jetting of a compressed air at saidcorrecting device (47).
 3. A laminating method as set forth in claim 2,wherein said negative pressure formed at said correcting device iscontrolled so as to reduce the height of said separator between asealant-applied surface applied with said sealant and a correctedsurface to be corrected in warping, to or below a predetermined value.4. An apparatus for laminating a separator and a membrane/electrodeassembly for use as a fuel cell, said apparatus comprising: a pallet(81) on which said separator (78) applied with a sealant (97) is placed;and a correcting device (47) for correcting a warp in said separator;wherein, said membrane/electrode assembly is superimposed on saidseparator with said correcting device being operated.
 5. A laminatingapparatus as set forth in claim 4, wherein said warp in said separatoris corrected by attracting and flattening said separator under anegative pressure formed by jetting of a compressed air at saidcorrecting device.
 6. A laminating apparatus as set forth in claim 5,wherein said negative pressure formed at said correcting device iscontrolled so as to reduce the height of said separator between asealant-applied surface applied with said sealant and a correctedsurface to be corrected in warping, to or below a predetermined value.